2026-09-22T00:10:59Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/67290 2023-07-11 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

Haines, David Richard 2014-12-13T20:11:23Z 2014-12-13T20:11:23Z 10000-01-01 1981 1981 Ribosidation of a series of azolinones was achieved via silylation and SnCl(,4) catalysis. Ribosidation of 4-imidazolin-2-one gave 1-(beta)-D-ribofuranosyl-4-imidazolin-2-one; of 1,2,4-triazolin-3-one gave 1-, 2-, and 4-(beta)-D-ribofuranosyl-1,2,4-triazolin-3-one, and 2,4-bis-(beta)-D-ribofuranosyl-1,2,4-triazolin-3-one; and of 2-tetrazolin-5-one gave 1-(beta)-D-ribofuranosyl-2-tetrazolin-5-one and 1,4-bis-(beta)-D-ribofuranosyl-2-tetrazolin-5-one. Structure assignments were based on microanalyses and ('1)H and ('13)C NMR spectra. The triazolinone mono-riboside isomer structures are differentiated by ('13)C NMR long-range coupling patterns, and two of the assignments were confirmed by X-ray crystallography. Improved syntheses were developed for two of the ribosides by fashioning the azolinone rings onto 2,3,5-tri-O-benzoylribofuranosyl isocyanate. Reaction of 2,3,5-tri-O-benzoylribofuranosyl isocyanate with (alpha)-aminoacetaldehyde diethyl acetal gave N-(2,2-diethoxyethyl)-N'-(beta)-D-(2,3,5-tri-O-benzoylribofuranosyl)-4-imidazolin-2-one in the presence of acid. Addition of formic acid hydrazide to 2,3,5-tri-O-benzoylribofuranosyl isocyanate gave 1-formyl-4-(beta)-D-(2,3,5-tri-O-benzoyl-ribofuranosyl)semicarbazide, which gave 4-(beta)-D-(2,3,5-tri-O-benzoylribofuranosyl)-1,2,4-triazolin-3-one upon dehydrative silylation. Methyl N-carbomethoxyformimidate was synthesized as a possible reagent for the synthesis of the other 1,2,4-triazolin-3-one products. Carbamoylation of 4-imidazolin-2-one, 1,2,4-triazolin-3-one, and 2-tetrazolin-5-one was achieved using either trimethylsilyl isocyanate or phosgene and ammonia, giving 1-carbamoyl-4-imidazolin-2-one, 2- and 4-carbamoyl-1,2,4-triazolin-3-one, and 1-carbamoyl-2-tetrazolin-5-one, respectively. Protection of nucleosides with t-butyldimethylsilyl chloride permitted carbamoylation on the heterocyclic base using trimethylsilyl isocyanate. Protection of inosine gave 2',3',5'-tri-O-t-butyldimethylsilylinosine, which was carbamoylated to give 1-carbamoyl-2',3',5'-tri-O-t-butyldimethylsilylinosine. Made available in DSpace on 2014-12-13T20:11:23Z (GMT). No. of bitstreams: 1 8203477.pdf: 2614017 bytes, checksum: 6ef4245e94c503a6bf3ab56ce9bb2bb1 (MD5) Previous issue date: 1981 Embargo set by: Seth Robbins for item 67468 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 92 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981. http://hdl.handle.net/2142/67290 (UMI)AAI8203477 eng Chemistry, Organic Synthesis and Structure Assignments of Novel Azolinone Ribonucleosides text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.